Fig. 21. Adjusting the throttle setting.
û. Check that the fuel-air mixture is correct on
both carburetors. First lift the piston on one
of the carburetors slightly by means of the pin
beside the air intake. Then release the pin and
carry out the same procedure on the other
carburetor.
The degree of uneven running on the engine
should be the same in both cases.
I f the engine stalls when the piston on one of
the carburetors is lifted, this usually means
that the mixture on the other carburetor is too
lean. The jet adjuster nut on the carburetor in
question should be screwed carefully down-
wards to remedy this.
7. Connect the carburetors together by tightening
the couplings on the shaft. Check that air flow
i s equal on both carburetors. See point 4.
Adjust idling speed to 500-700 r.p.m. by using
the idling adjuster screws. Adjust the rapid
idling screws. This is done by screwing each
screw until it is in contact with the cam plate
and then screwing it back until a certain clear-
ance is obtained.
Rapid idling and choke control
mechanism
When the choke control is completely pushed in,
the clearance between the adjuster screw (4,
Fig. 4) and the cam plate should correspond to
' /2
to 1 turn.
The clamp on the end of the choke cable should
be attached so that the jets begin to go down
when the choke button on the instrument panel
has been pulled out about
1
/2"
(rapid idling move-
ment). Increased resistance will be felt on the
choke button when the jets begin to move down-
wards.
When the choke control button is pulled out as
far as it will go, the long lever ends should be
lifted so far that the jets are completely lowered,
i. e. the levers should contact the stops in the
li nks. Make sure that both levers are influenced
to the same extent through the curved cable so
that both jets start to move downwards at the
same time.
Throttle setting
The position of the accelerator pedal should be
adjusted so that there is a clearance of 0.060"
(1.5 mm) between the stop arm and full-throttle
stop when the accelerator pedal is fully depressed.
This will give the pedal the correct height above
the floor and will also unload the control to a
certain extent.
When adjusting, loosen the coupling (4, Fig. 21),
place a weight on the pedal so that it is pressed
down fully, adjust the clearance and then tighten
the coupling.
N.B. The clearance must not exceed 0.080" (2 mm)
as this will reduce the output. (On early production
there is a lever in front of the carburetor instead
of the coupling (4).
The shaft between the carburetors is fitted so that
the end float is distributed equally at both ends.
I n cases where the coupling behind the rear
carburetor is in the form of a ridged spring, ensure
that there is clearance between the shaft ends
before tightening.
Air cleaners
The air cleaners with wire wool should be dis-
assembled for cleaning after every 3000 miles.
Clean the filters in clean kerosene and blow then
dry with compressed air. Then soak them in en-
gine oil, let the excess oil run off and re-assemble
them.
Air cleaners with paper cartridges must not be
washed or oiled in.
They should be replaced after every 12,500 miles.
I f the vehicle is used in very dusty or contaminated
1. Feeler
gauge, 1.5 mm 3. Lever
2. Full throttle stop
4. Coupling